The present invention relates to an interface circuit for use between a sensor with capacitive impedance, particularly a piezoelectric accelerometric sensor, and a circuit for processing the signal provided by the sensor, particularly a filtering circuit with switched capacitors.
Piezoelectric accelerometric sensors are used, for example, in systems for detecting pinking (knocking) in Otto-cycle internal combustion engines for motor vehicles. In this type of application, the signal provided by a piezoelectric accelerometric sensor is processed by processing circuits which include, in particular, integrated filtering circuits of the type with switched capacitors.